Serbian President Boris Tadic told the visiting United Nations chief war crimes prosecutor Tuesday that Serbia is making every effort to capture remaining war crimes suspects.

Prosecutor Serge Brammertz is in Belgrade to review Serbia's cooperation with the U.N. war crimes tribunal in The Hague. President Tadic and Prime Minister Mirko Cvetkovic said Serbian authorities are fully cooperating with the tribunal.

Belgrade's cooperation with the court is a condition to signing a key aid and trade agreement with the European Union.

Brammertz is in Belgrade for a two-day visit ending Tuesday. He is due to submit a regular six-monthly report on Serbia's cooperation with The Hague tribunal to the U.N. Security Council later this month.

Rasim Ljajic, who heads Serbia's Action Team for war crimes, acknowledged that the prosecutor's report cannot not be positive until Serbia delivers the top war crimes fugitive suspect to the Hague. He said he believes Serbian authorities currently have little hope of capturing Bosnian Serb wartime commander Ratko Mladic, who is wanted by the Hague.

The E.U. has made the delivery of the top war crimes suspects a key condition to signing a Stabilization and Association Agreement with Serbia. The accord is a first step toward gaining candidacy for membership in the 27-nation bloc.

Mladic has been on the run since 1995. Serbian police earlier this year arrested the other top war crimes fugitive, Bosnian Serb political leader Radovan Karadzic and delivered him to the Hague.